Hundreds of police officers will vanish from the streets by 2019, when £126m will have been slashed from the budget in nine years.

More than 1,200 officers, PCSOs and staff have left since 2010 - and another 800 are expected to go over the next two years.

Around 40% of the workforce will have left at the end of that nine year period.

Sir Jon, 56, today warned how the savage cuts – recently described as “catastrophic” by police commissioner Jane Kennedy – had left the force with no option to review the service it delivers.

Speaking bluntly, he told how traditional bobbies on the beat face being sacrificed as resources continue to shrink.

Sir Jon said: “We have to configure ourselves to make sure we address those issues which are most important to the public.

“We have to always answer the phone, which is one million calls a year, and we have to respond to those calls.

“We have to protect the vulnerable - young people facing neglect, abuse or exploitation, victims of domestic abuse, the elderly and those suffering mental health issues.

“We deal with 34,000 domestic abuse incidents each year and 376 vulnerable missing-from-home enquiries a month.

“On top of that we have to deal with those involved in serious, organised crime - drug trafficking, gun crime, robberies and money laundering.

“We have to investigate the crimes which are reported to us and do everything in our power to put bad people behind bars.

“When we have done all that, there’s an expectation that we will deliver neighbourhood policing with the people who are left.

“Over the next two years that’s going to be a significantly smaller pool of people and neighbourhood policing as people understand it - visible bobbies on the beat, wearing big hats - will not be possible.

“We will endeavour to continue to provide neighbourhood policing but we will be forced to do it in a different way.

“It comes down to are you going to deal with protecting vulnerable people or are you going to pander to the political pressure of having bobbies on the beat?

“This is the stark reality of where we are.”

Sir Jon also told how growing cyber crime is also putting huge pressure on resources and the difficulty in dealing with soaring volumes of historical sex enquiries launched in the wake of the Jimmy Savile scandal.

He said: “A particular challenge going forward will be our ability to deal with historical enquiries. As a consequence of Savile, there has been a massive increase in reports of all forms of sexual abuse.

“In particular, sexual abuse in care homes and sexual abuse committed at the hands of those in power.

“These events have left lifelong traumatic scars on victims, and they deserve justice.

“But our ability to deliver this at the same time as keeping children safe today is going to be very difficult.

“It is a challenge we will have to rise to.”

Yet Sir Jon said he remained proud to lead the organisation “whatever the challenges we currently face”.

He added: “I have the great privilege of being chief constable of the force I joined 40 years ago in the city I was born.

“I was born and bred in the communities of Liverpool, as the vast majority of officers were.

“It’s a huge privilege to lead them.

“They are a fantastic group of people who do a great job, day-in, day-out, in increasingly difficult circumstances.”